// Copyright 2015 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "src/wasm/wasm-objects.h"
#include "src/utils.h"
#include "src/assembler-inl.h"
#include "src/base/iterator.h"
#include "src/code-factory.h"
#include "src/compiler/wasm-compiler.h"
#include "src/debug/debug-interface.h"
#include "src/objects-inl.h"
#include "src/objects/debug-objects-inl.h"
#include "src/objects/shared-function-info.h"
#include "src/trap-handler/trap-handler.h"
#include "src/wasm/jump-table-assembler.h"
#include "src/wasm/module-compiler.h"
#include "src/wasm/module-decoder.h"
#include "src/wasm/wasm-code-manager.h"
#include "src/wasm/wasm-engine.h"
#include "src/wasm/wasm-limits.h"
#include "src/wasm/wasm-memory.h"
#include "src/wasm/wasm-module.h"
#include "src/wasm/wasm-objects-inl.h"
#include "src/wasm/wasm-text.h"
#define TRACE(...) \
do { \
if (FLAG_trace_wasm_instances) PrintF(__VA_ARGS__); \
} while (false)
#define TRACE_IFT(...) \
do { \
if (false) PrintF(__VA_ARGS__); \
} while (false)
namespace v8 {
namespace internal {
// Import a few often used types from the wasm namespace.
using WasmFunction = wasm::WasmFunction;
using WasmModule = wasm::WasmModule;
namespace {
// Manages the natively-allocated memory for a WasmInstanceObject. Since
// an instance finalizer is not guaranteed to run upon isolate shutdown,
// we must use a Managed<WasmInstanceNativeAllocations> to guarantee
// it is freed.
// Native allocations are the signature ids and targets for indirect call
// targets, as well as the call targets for imported functions.
class WasmInstanceNativeAllocations {
public:
// Helper macro to set an internal field and the corresponding field
// on an instance.
#define SET(instance, field, value) \
{ \
auto v = value; \
this->field##_ = v; \
instance->set_##field(v); \
}
// Allocates initial native storage for a given instance.
WasmInstanceNativeAllocations(Handle<WasmInstanceObject> instance,
size_t num_imported_functions,
size_t num_imported_mutable_globals) {
SET(instance, imported_function_targets,
reinterpret_cast<Address*>(
calloc(num_imported_functions, sizeof(Address))));
SET(instance, imported_mutable_globals,
reinterpret_cast<Address*>(
calloc(num_imported_mutable_globals, sizeof(Address))));
}
~WasmInstanceNativeAllocations() {
::free(indirect_function_table_sig_ids_);
indirect_function_table_sig_ids_ = nullptr;
::free(indirect_function_table_targets_);
indirect_function_table_targets_ = nullptr;
::free(imported_function_targets_);
imported_function_targets_ = nullptr;
::free(imported_mutable_globals_);
imported_mutable_globals_ = nullptr;
}
// Resizes the indirect function table.
void resize_indirect_function_table(Isolate* isolate,
Handle<WasmInstanceObject> instance,
uint32_t new_size) {
uint32_t old_size = instance->indirect_function_table_size();
void* new_sig_ids = nullptr;
void* new_targets = nullptr;
Handle<FixedArray> new_instances;
if (indirect_function_table_sig_ids_) {
// Reallocate the old storage.
new_sig_ids = realloc(indirect_function_table_sig_ids_,
new_size * sizeof(uint32_t));
new_targets =
realloc(indirect_function_table_targets_, new_size * sizeof(Address));
Handle<FixedArray> old(instance->indirect_function_table_instances(),
isolate);
new_instances = isolate->factory()->CopyFixedArrayAndGrow(
old, static_cast<int>(new_size - old_size));
} else {
// Allocate new storage.
new_sig_ids = malloc(new_size * sizeof(uint32_t));
new_targets = malloc(new_size * sizeof(Address));
new_instances =
isolate->factory()->NewFixedArray(static_cast<int>(new_size));
}
// Initialize new entries.
instance->set_indirect_function_table_size(new_size);
SET(instance, indirect_function_table_sig_ids,
reinterpret_cast<uint32_t*>(new_sig_ids));
SET(instance, indirect_function_table_targets,
reinterpret_cast<Address*>(new_targets));
instance->set_indirect_function_table_instances(*new_instances);
for (uint32_t j = old_size; j < new_size; j++) {
IndirectFunctionTableEntry(instance, static_cast<int>(j)).clear();
}
}
uint32_t* indirect_function_table_sig_ids_ = nullptr;
Address* indirect_function_table_targets_ = nullptr;
Address* imported_function_targets_ = nullptr;
Address* imported_mutable_globals_ = nullptr;
#undef SET
};
size_t EstimateNativeAllocationsSize(const WasmModule* module) {
size_t estimate = sizeof(WasmInstanceNativeAllocations) +
(1 * kPointerSize * module->num_imported_mutable_globals) +
(2 * kPointerSize * module->num_imported_functions);
for (auto& table : module->tables) {
estimate += 3 * kPointerSize * table.initial_size;
}
return estimate;
}
WasmInstanceNativeAllocations* GetNativeAllocations(
WasmInstanceObject* instance) {
return reinterpret_cast<Managed<WasmInstanceNativeAllocations>*>(
instance->managed_native_allocations())
->raw();
}
#ifdef DEBUG
bool IsBreakablePosition(wasm::NativeModule* native_module, int func_index,
int offset_in_func) {
AccountingAllocator alloc;
Zone tmp(&alloc, ZONE_NAME);
wasm::BodyLocalDecls locals(&tmp);
const byte* module_start = native_module->wire_bytes().start();
const WasmFunction& func = native_module->module()->functions[func_index];
wasm::BytecodeIterator iterator(module_start + func.code.offset(),
module_start + func.code.end_offset(),
&locals);
DCHECK_LT(0, locals.encoded_size);
for (uint32_t offset : iterator.offsets()) {
if (offset > static_cast<uint32_t>(offset_in_func)) break;
if (offset == static_cast<uint32_t>(offset_in_func)) return true;
}
return false;
}
#endif // DEBUG
enum DispatchTableElements : int {
kDispatchTableInstanceOffset,
kDispatchTableIndexOffset,
kDispatchTableFunctionTableOffset,
// Marker:
kDispatchTableNumElements
};
} // namespace
// static
Handle<WasmModuleObject> WasmModuleObject::New(
Isolate* isolate, const wasm::WasmFeatures& enabled,
std::shared_ptr<const wasm::WasmModule> shared_module, wasm::ModuleEnv& env,
OwnedVector<const uint8_t> wire_bytes, Handle<Script> script,
Handle<ByteArray> asm_js_offset_table) {
DCHECK_EQ(shared_module.get(), env.module);
// Create a new {NativeModule} first.
size_t native_memory_estimate =
isolate->wasm_engine()->code_manager()->EstimateNativeModuleSize(
env.module);
auto native_module = isolate->wasm_engine()->code_manager()->NewNativeModule(
isolate, enabled, native_memory_estimate,
wasm::NativeModule::kCanAllocateMoreMemory, std::move(shared_module),
env);
native_module->set_wire_bytes(std::move(wire_bytes));
native_module->SetRuntimeStubs(isolate);
// Delegate to the shared {WasmModuleObject::New} allocator.
Handle<WasmModuleObject> module_object =
New(isolate, std::move(native_module), script);
if (!asm_js_offset_table.is_null()) {
module_object->set_asm_js_offset_table(*asm_js_offset_table);
}
return module_object;
}
// static
Handle<WasmModuleObject> WasmModuleObject::New(
Isolate* isolate, std::shared_ptr<wasm::NativeModule> native_module,
Handle<Script> script) {
int export_wrapper_size =
static_cast<int>(native_module->module()->num_exported_functions);
Handle<FixedArray> export_wrappers =
isolate->factory()->NewFixedArray(export_wrapper_size, TENURED);
// Use the given shared {NativeModule}, but increase its reference count by
// allocating a new {Managed<T>} that the {WasmModuleObject} references.
size_t native_memory_estimate =
isolate->wasm_engine()->code_manager()->EstimateNativeModuleSize(
native_module->module());
size_t memory_estimate =
EstimateWasmModuleSize(native_module->module()) + native_memory_estimate;
Handle<Managed<wasm::NativeModule>> managed_native_module =
Managed<wasm::NativeModule>::FromSharedPtr(isolate, memory_estimate,
std::move(native_module));
Handle<WasmModuleObject> module_object = Handle<WasmModuleObject>::cast(
isolate->factory()->NewJSObject(isolate->wasm_module_constructor()));
module_object->set_export_wrappers(*export_wrappers);
if (script->type() == Script::TYPE_WASM) {
script->set_wasm_module_object(*module_object);
}
module_object->set_script(*script);
module_object->set_weak_instance_list(
ReadOnlyRoots(isolate).empty_weak_array_list());
module_object->set_managed_native_module(*managed_native_module);
return module_object;
}
bool WasmModuleObject::SetBreakPoint(Handle<WasmModuleObject> module_object,
int* position,
Handle<BreakPoint> break_point) {
Isolate* isolate = module_object->GetIsolate();
// Find the function for this breakpoint.
int func_index = module_object->GetContainingFunction(*position);
if (func_index < 0) return false;
const WasmFunction& func = module_object->module()->functions[func_index];
int offset_in_func = *position - func.code.offset();
// According to the current design, we should only be called with valid
// breakable positions.
DCHECK(IsBreakablePosition(module_object->native_module(), func_index,
offset_in_func));
// Insert new break point into break_positions of module object.
WasmModuleObject::AddBreakpoint(module_object, *position, break_point);
// Iterate over all instances of this module and tell them to set this new
// breakpoint. We do this using the weak list of all instances.
Handle<WeakArrayList> weak_instance_list(module_object->weak_instance_list(),
isolate);
for (int i = 0; i < weak_instance_list->length(); ++i) {
MaybeObject* maybe_instance = weak_instance_list->Get(i);
if (maybe_instance->IsWeak()) {
Handle<WasmInstanceObject> instance(
WasmInstanceObject::cast(maybe_instance->GetHeapObjectAssumeWeak()),
isolate);
Handle<WasmDebugInfo> debug_info =
WasmInstanceObject::GetOrCreateDebugInfo(instance);
WasmDebugInfo::SetBreakpoint(debug_info, func_index, offset_in_func);
}
}
return true;
}
namespace {
int GetBreakpointPos(Isolate* isolate, Object* break_point_info_or_undef) {
if (break_point_info_or_undef->IsUndefined(isolate)) return kMaxInt;
return BreakPointInfo::cast(break_point_info_or_undef)->source_position();
}
int FindBreakpointInfoInsertPos(Isolate* isolate,
Handle<FixedArray> breakpoint_infos,
int position) {
// Find insert location via binary search, taking care of undefined values on
// the right. Position is always greater than zero.
DCHECK_LT(0, position);
int left = 0; // inclusive
int right = breakpoint_infos->length(); // exclusive
while (right - left > 1) {
int mid = left + (right - left) / 2;
Object* mid_obj = breakpoint_infos->get(mid);
if (GetBreakpointPos(isolate, mid_obj) <= position) {
left = mid;
} else {
right = mid;
}
}
int left_pos = GetBreakpointPos(isolate, breakpoint_infos->get(left));
return left_pos < position ? left + 1 : left;
}
} // namespace
void WasmModuleObject::AddBreakpoint(Handle<WasmModuleObject> module_object,
int position,
Handle<BreakPoint> break_point) {
Isolate* isolate = module_object->GetIsolate();
Handle<FixedArray> breakpoint_infos;
if (module_object->has_breakpoint_infos()) {
breakpoint_infos = handle(module_object->breakpoint_infos(), isolate);
} else {
breakpoint_infos = isolate->factory()->NewFixedArray(4, TENURED);
module_object->set_breakpoint_infos(*breakpoint_infos);
}
int insert_pos =
FindBreakpointInfoInsertPos(isolate, breakpoint_infos, position);
// If a BreakPointInfo object already exists for this position, add the new
// breakpoint object and return.
if (insert_pos < breakpoint_infos->length() &&
GetBreakpointPos(isolate, breakpoint_infos->get(insert_pos)) ==
position) {
Handle<BreakPointInfo> old_info(
BreakPointInfo::cast(breakpoint_infos->get(insert_pos)), isolate);
BreakPointInfo::SetBreakPoint(isolate, old_info, break_point);
return;
}
// Enlarge break positions array if necessary.
bool need_realloc = !breakpoint_infos->get(breakpoint_infos->length() - 1)
->IsUndefined(isolate);
Handle<FixedArray> new_breakpoint_infos = breakpoint_infos;
if (need_realloc) {
new_breakpoint_infos = isolate->factory()->NewFixedArray(
2 * breakpoint_infos->length(), TENURED);
module_object->set_breakpoint_infos(*new_breakpoint_infos);
// Copy over the entries [0, insert_pos).
for (int i = 0; i < insert_pos; ++i)
new_breakpoint_infos->set(i, breakpoint_infos->get(i));
}
// Move elements [insert_pos, ...] up by one.
for (int i = breakpoint_infos->length() - 1; i >= insert_pos; --i) {
Object* entry = breakpoint_infos->get(i);
if (entry->IsUndefined(isolate)) continue;
new_breakpoint_infos->set(i + 1, entry);
}
// Generate new BreakpointInfo.
Handle<BreakPointInfo> breakpoint_info =
isolate->factory()->NewBreakPointInfo(position);
BreakPointInfo::SetBreakPoint(isolate, breakpoint_info, break_point);
// Now insert new position at insert_pos.
new_breakpoint_infos->set(insert_pos, *breakpoint_info);
}
void WasmModuleObject::SetBreakpointsOnNewInstance(
Handle<WasmModuleObject> module_object,
Handle<WasmInstanceObject> instance) {
if (!module_object->has_breakpoint_infos()) return;
Isolate* isolate = module_object->GetIsolate();
Handle<WasmDebugInfo> debug_info =
WasmInstanceObject::GetOrCreateDebugInfo(instance);
Handle<FixedArray> breakpoint_infos(module_object->breakpoint_infos(),
isolate);
// If the array exists, it should not be empty.
DCHECK_LT(0, breakpoint_infos->length());
for (int i = 0, e = breakpoint_infos->length(); i < e; ++i) {
Handle<Object> obj(breakpoint_infos->get(i), isolate);
if (obj->IsUndefined(isolate)) {
for (; i < e; ++i) {
DCHECK(breakpoint_infos->get(i)->IsUndefined(isolate));
}
break;
}
Handle<BreakPointInfo> breakpoint_info = Handle<BreakPointInfo>::cast(obj);
int position = breakpoint_info->source_position();
// Find the function for this breakpoint, and set the breakpoint.
int func_index = module_object->GetContainingFunction(position);
DCHECK_LE(0, func_index);
const WasmFunction& func = module_object->module()->functions[func_index];
int offset_in_func = position - func.code.offset();
WasmDebugInfo::SetBreakpoint(debug_info, func_index, offset_in_func);
}
}
namespace {
enum AsmJsOffsetTableEntryLayout {
kOTEByteOffset,
kOTECallPosition,
kOTENumberConvPosition,
kOTESize
};
Handle<ByteArray> GetDecodedAsmJsOffsetTable(
Handle<WasmModuleObject> module_object, Isolate* isolate) {
DCHECK(module_object->is_asm_js());
Handle<ByteArray> offset_table(module_object->asm_js_offset_table(), isolate);
// The last byte in the asm_js_offset_tables ByteArray tells whether it is
// still encoded (0) or decoded (1).
enum AsmJsTableType : int { Encoded = 0, Decoded = 1 };
int table_type = offset_table->get(offset_table->length() - 1);
DCHECK(table_type == Encoded || table_type == Decoded);
if (table_type == Decoded) return offset_table;
wasm::AsmJsOffsetsResult asm_offsets;
{
DisallowHeapAllocation no_gc;
byte* bytes_start = offset_table->GetDataStartAddress();
byte* bytes_end = reinterpret_cast<byte*>(
reinterpret_cast<Address>(bytes_start) + offset_table->length() - 1);
asm_offsets = wasm::DecodeAsmJsOffsets(bytes_start, bytes_end);
}
// Wasm bytes must be valid and must contain asm.js offset table.
DCHECK(asm_offsets.ok());
DCHECK_GE(kMaxInt, asm_offsets.val.size());
int num_functions = static_cast<int>(asm_offsets.val.size());
int num_imported_functions =
static_cast<int>(module_object->module()->num_imported_functions);
DCHECK_EQ(module_object->module()->functions.size(),
static_cast<size_t>(num_functions) + num_imported_functions);
int num_entries = 0;
for (int func = 0; func < num_functions; ++func) {
size_t new_size = asm_offsets.val[func].size();
DCHECK_LE(new_size, static_cast<size_t>(kMaxInt) - num_entries);
num_entries += static_cast<int>(new_size);
}
// One byte to encode that this is a decoded table.
DCHECK_GE(kMaxInt,
1 + static_cast<uint64_t>(num_entries) * kOTESize * kIntSize);
int total_size = 1 + num_entries * kOTESize * kIntSize;
Handle<ByteArray> decoded_table =
isolate->factory()->NewByteArray(total_size, TENURED);
decoded_table->set(total_size - 1, AsmJsTableType::Decoded);
module_object->set_asm_js_offset_table(*decoded_table);
int idx = 0;
const std::vector<WasmFunction>& wasm_funs =
module_object->module()->functions;
for (int func = 0; func < num_functions; ++func) {
std::vector<wasm::AsmJsOffsetEntry>& func_asm_offsets =
asm_offsets.val[func];
if (func_asm_offsets.empty()) continue;
int func_offset = wasm_funs[num_imported_functions + func].code.offset();
for (wasm::AsmJsOffsetEntry& e : func_asm_offsets) {
// Byte offsets must be strictly monotonously increasing:
DCHECK_IMPLIES(idx > 0, func_offset + e.byte_offset >
decoded_table->get_int(idx - kOTESize));
decoded_table->set_int(idx + kOTEByteOffset, func_offset + e.byte_offset);
decoded_table->set_int(idx + kOTECallPosition, e.source_position_call);
decoded_table->set_int(idx + kOTENumberConvPosition,
e.source_position_number_conversion);
idx += kOTESize;
}
}
DCHECK_EQ(total_size, idx * kIntSize + 1);
return decoded_table;
}
} // namespace
int WasmModuleObject::GetSourcePosition(Handle<WasmModuleObject> module_object,
uint32_t func_index,
uint32_t byte_offset,
bool is_at_number_conversion) {
Isolate* isolate = module_object->GetIsolate();
const WasmModule* module = module_object->module();
if (module->origin != wasm::kAsmJsOrigin) {
// for non-asm.js modules, we just add the function's start offset
// to make a module-relative position.
return byte_offset + module_object->GetFunctionOffset(func_index);
}
// asm.js modules have an additional offset table that must be searched.
Handle<ByteArray> offset_table =
GetDecodedAsmJsOffsetTable(module_object, isolate);
DCHECK_LT(func_index, module->functions.size());
uint32_t func_code_offset = module->functions[func_index].code.offset();
uint32_t total_offset = func_code_offset + byte_offset;
// Binary search for the total byte offset.
int left = 0; // inclusive
int right = offset_table->length() / kIntSize / kOTESize; // exclusive
DCHECK_LT(left, right);
while (right - left > 1) {
int mid = left + (right - left) / 2;
int mid_entry = offset_table->get_int(kOTESize * mid);
DCHECK_GE(kMaxInt, mid_entry);
if (static_cast<uint32_t>(mid_entry) <= total_offset) {
left = mid;
} else {
right = mid;
}
}
// There should be an entry for each position that could show up on the stack
// trace:
DCHECK_EQ(total_offset, offset_table->get_int(kOTESize * left));
int idx = is_at_number_conversion ? kOTENumberConvPosition : kOTECallPosition;
return offset_table->get_int(kOTESize * left + idx);
}
v8::debug::WasmDisassembly WasmModuleObject::DisassembleFunction(
int func_index) {
DisallowHeapAllocation no_gc;
if (func_index < 0 ||
static_cast<uint32_t>(func_index) >= module()->functions.size())
return {};
Vector<const byte> wire_bytes = native_module()->wire_bytes();
std::ostringstream disassembly_os;
v8::debug::WasmDisassembly::OffsetTable offset_table;
PrintWasmText(module(), wire_bytes, static_cast<uint32_t>(func_index),
disassembly_os, &offset_table);
return {disassembly_os.str(), std::move(offset_table)};
}
bool WasmModuleObject::GetPossibleBreakpoints(
const v8::debug::Location& start, const v8::debug::Location& end,
std::vector<v8::debug::BreakLocation>* locations) {
DisallowHeapAllocation no_gc;
const std::vector<WasmFunction>& functions = module()->functions;
if (start.GetLineNumber() < 0 || start.GetColumnNumber() < 0 ||
(!end.IsEmpty() &&
(end.GetLineNumber() < 0 || end.GetColumnNumber() < 0)))
return false;
// start_func_index, start_offset and end_func_index is inclusive.
// end_offset is exclusive.
// start_offset and end_offset are module-relative byte offsets.
uint32_t start_func_index = start.GetLineNumber();
if (start_func_index >= functions.size()) return false;
int start_func_len = functions[start_func_index].code.length();
if (start.GetColumnNumber() > start_func_len) return false;
uint32_t start_offset =
functions[start_func_index].code.offset() + start.GetColumnNumber();
uint32_t end_func_index;
uint32_t end_offset;
if (end.IsEmpty()) {
// Default: everything till the end of the Script.
end_func_index = static_cast<uint32_t>(functions.size() - 1);
end_offset = functions[end_func_index].code.end_offset();
} else {
// If end is specified: Use it and check for valid input.
end_func_index = static_cast<uint32_t>(end.GetLineNumber());
// Special case: Stop before the start of the next function. Change to: Stop
// at the end of the function before, such that we don't disassemble the
// next function also.
if (end.GetColumnNumber() == 0 && end_func_index > 0) {
--end_func_index;
end_offset = functions[end_func_index].code.end_offset();
} else {
if (end_func_index >= functions.size()) return false;
end_offset =
functions[end_func_index].code.offset() + end.GetColumnNumber();
if (end_offset > functions[end_func_index].code.end_offset())
return false;
}
}
AccountingAllocator alloc;
Zone tmp(&alloc, ZONE_NAME);
const byte* module_start = native_module()->wire_bytes().start();
for (uint32_t func_idx = start_func_index; func_idx <= end_func_index;
++func_idx) {
const WasmFunction& func = functions[func_idx];
if (func.code.length() == 0) continue;
wasm::BodyLocalDecls locals(&tmp);
wasm::BytecodeIterator iterator(module_start + func.code.offset(),
module_start + func.code.end_offset(),
&locals);
DCHECK_LT(0u, locals.encoded_size);
for (uint32_t offset : iterator.offsets()) {
uint32_t total_offset = func.code.offset() + offset;
if (total_offset >= end_offset) {
DCHECK_EQ(end_func_index, func_idx);
break;
}
if (total_offset < start_offset) continue;
locations->emplace_back(func_idx, offset, debug::kCommonBreakLocation);
}
}
return true;
}
MaybeHandle<FixedArray> WasmModuleObject::CheckBreakPoints(
Isolate* isolate, Handle<WasmModuleObject> module_object, int position) {
if (!module_object->has_breakpoint_infos()) return {};
Handle<FixedArray> breakpoint_infos(module_object->breakpoint_infos(),
isolate);
int insert_pos =
FindBreakpointInfoInsertPos(isolate, breakpoint_infos, position);
if (insert_pos >= breakpoint_infos->length()) return {};
Handle<Object> maybe_breakpoint_info(breakpoint_infos->get(insert_pos),
isolate);
if (maybe_breakpoint_info->IsUndefined(isolate)) return {};
Handle<BreakPointInfo> breakpoint_info =
Handle<BreakPointInfo>::cast(maybe_breakpoint_info);
if (breakpoint_info->source_position() != position) return {};
// There is no support for conditional break points. Just assume that every
// break point always hits.
Handle<Object> break_points(breakpoint_info->break_points(), isolate);
if (break_points->IsFixedArray()) {
return Handle<FixedArray>::cast(break_points);
}
Handle<FixedArray> break_points_hit = isolate->factory()->NewFixedArray(1);
break_points_hit->set(0, *break_points);
return break_points_hit;
}
MaybeHandle<String> WasmModuleObject::ExtractUtf8StringFromModuleBytes(
Isolate* isolate, Handle<WasmModuleObject> module_object,
wasm::WireBytesRef ref) {
// TODO(wasm): cache strings from modules if it's a performance win.
Vector<const uint8_t> wire_bytes =
module_object->native_module()->wire_bytes();
return ExtractUtf8StringFromModuleBytes(isolate, wire_bytes, ref);
}
MaybeHandle<String> WasmModuleObject::ExtractUtf8StringFromModuleBytes(
Isolate* isolate, Vector<const uint8_t> wire_bytes,
wasm::WireBytesRef ref) {
Vector<const uint8_t> name_vec = wire_bytes + ref.offset();
name_vec.Truncate(ref.length());
// UTF8 validation happens at decode time.
DCHECK(unibrow::Utf8::ValidateEncoding(name_vec.start(), name_vec.length()));
return isolate->factory()->NewStringFromUtf8(
Vector<const char>::cast(name_vec));
}
MaybeHandle<String> WasmModuleObject::GetModuleNameOrNull(
Isolate* isolate, Handle<WasmModuleObject> module_object) {
const WasmModule* module = module_object->module();
if (!module->name.is_set()) return {};
return ExtractUtf8StringFromModuleBytes(isolate, module_object, module->name);
}
MaybeHandle<String> WasmModuleObject::GetFunctionNameOrNull(
Isolate* isolate, Handle<WasmModuleObject> module_object,
uint32_t func_index) {
DCHECK_LT(func_index, module_object->module()->functions.size());
wasm::WireBytesRef name = module_object->module()->LookupFunctionName(
wasm::ModuleWireBytes(module_object->native_module()->wire_bytes()),
func_index);
if (!name.is_set()) return {};
return ExtractUtf8StringFromModuleBytes(isolate, module_object, name);
}
Handle<String> WasmModuleObject::GetFunctionName(
Isolate* isolate, Handle<WasmModuleObject> module_object,
uint32_t func_index) {
MaybeHandle<String> name =
GetFunctionNameOrNull(isolate, module_object, func_index);
if (!name.is_null()) return name.ToHandleChecked();
EmbeddedVector<char, 32> buffer;
int length = SNPrintF(buffer, "wasm-function[%u]", func_index);
return isolate->factory()
->NewStringFromOneByte(Vector<uint8_t>::cast(buffer.SubVector(0, length)))
.ToHandleChecked();
}
Vector<const uint8_t> WasmModuleObject::GetRawFunctionName(
uint32_t func_index) {
DCHECK_GT(module()->functions.size(), func_index);
wasm::ModuleWireBytes wire_bytes(native_module()->wire_bytes());
wasm::WireBytesRef name_ref =
module()->LookupFunctionName(wire_bytes, func_index);
wasm::WasmName name = wire_bytes.GetNameOrNull(name_ref);
return Vector<const uint8_t>::cast(name);
}
int WasmModuleObject::GetFunctionOffset(uint32_t func_index) {
const std::vector<WasmFunction>& functions = module()->functions;
if (static_cast<uint32_t>(func_index) >= functions.size()) return -1;
DCHECK_GE(kMaxInt, functions[func_index].code.offset());
return static_cast<int>(functions[func_index].code.offset());
}
int WasmModuleObject::GetContainingFunction(uint32_t byte_offset) {
const std::vector<WasmFunction>& functions = module()->functions;
// Binary search for a function containing the given position.
int left = 0; // inclusive
int right = static_cast<int>(functions.size()); // exclusive
if (right == 0) return false;
while (right - left > 1) {
int mid = left + (right - left) / 2;
if (functions[mid].code.offset() <= byte_offset) {
left = mid;
} else {
right = mid;
}
}
// If the found function does not contains the given position, return -1.
const WasmFunction& func = functions[left];
if (byte_offset < func.code.offset() ||
byte_offset >= func.code.end_offset()) {
return -1;
}
return left;
}
bool WasmModuleObject::GetPositionInfo(uint32_t position,
Script::PositionInfo* info) {
if (script()->source_mapping_url()->IsString()) {
if (module()->functions.size() == 0) return false;
info->line = 0;
info->column = position;
info->line_start = module()->functions[0].code.offset();
info->line_end = module()->functions.back().code.end_offset();
return true;
}
int func_index = GetContainingFunction(position);
if (func_index < 0) return false;
const WasmFunction& function = module()->functions[func_index];
info->line = func_index;
info->column = position - function.code.offset();
info->line_start = function.code.offset();
info->line_end = function.code.end_offset();
return true;
}
Handle<WasmTableObject> WasmTableObject::New(Isolate* isolate, uint32_t initial,
int64_t maximum,
Handle<FixedArray>* js_functions) {
Handle<JSFunction> table_ctor(
isolate->native_context()->wasm_table_constructor(), isolate);
auto table_obj = Handle<WasmTableObject>::cast(
isolate->factory()->NewJSObject(table_ctor));
*js_functions = isolate->factory()->NewFixedArray(initial);
Object* null = ReadOnlyRoots(isolate).null_value();
for (int i = 0; i < static_cast<int>(initial); ++i) {
(*js_functions)->set(i, null);
}
table_obj->set_functions(**js_functions);
DCHECK_EQ(maximum, static_cast<int>(maximum));
Handle<Object> max = isolate->factory()->NewNumber(maximum);
table_obj->set_maximum_length(*max);
table_obj->set_dispatch_tables(ReadOnlyRoots(isolate).empty_fixed_array());
return Handle<WasmTableObject>::cast(table_obj);
}
void WasmTableObject::AddDispatchTable(Isolate* isolate,
Handle<WasmTableObject> table_obj,
Handle<WasmInstanceObject> instance,
int table_index) {
Handle<FixedArray> dispatch_tables(table_obj->dispatch_tables(), isolate);
int old_length = dispatch_tables->length();
DCHECK_EQ(0, old_length % kDispatchTableNumElements);
if (instance.is_null()) return;
// TODO(titzer): use weak cells here to avoid leaking instances.
// Grow the dispatch table and add a new entry at the end.
Handle<FixedArray> new_dispatch_tables =
isolate->factory()->CopyFixedArrayAndGrow(dispatch_tables,
kDispatchTableNumElements);
new_dispatch_tables->set(old_length + kDispatchTableInstanceOffset,
*instance);
new_dispatch_tables->set(old_length + kDispatchTableIndexOffset,
Smi::FromInt(table_index));
table_obj->set_dispatch_tables(*new_dispatch_tables);
}
void WasmTableObject::Grow(Isolate* isolate, uint32_t count) {
if (count == 0) return; // Degenerate case: nothing to do.
Handle<FixedArray> dispatch_tables(this->dispatch_tables(), isolate);
DCHECK_EQ(0, dispatch_tables->length() % kDispatchTableNumElements);
uint32_t old_size = functions()->length();
// Tables are stored in the instance object, no code patching is
// necessary. We simply have to grow the raw tables in each instance
// that has imported this table.
// TODO(titzer): replace the dispatch table with a weak list of all
// the instances that import a given table.
for (int i = 0; i < dispatch_tables->length();
i += kDispatchTableNumElements) {
Handle<WasmInstanceObject> instance(
WasmInstanceObject::cast(dispatch_tables->get(i)), isolate);
DCHECK_EQ(old_size, instance->indirect_function_table_size());
uint32_t new_size = old_size + count;
WasmInstanceObject::EnsureIndirectFunctionTableWithMinimumSize(instance,
new_size);
}
}
void WasmTableObject::Set(Isolate* isolate, Handle<WasmTableObject> table,
int32_t table_index, Handle<JSFunction> function) {
Handle<FixedArray> array(table->functions(), isolate);
if (function.is_null()) {
ClearDispatchTables(isolate, table, table_index); // Degenerate case.
array->set(table_index, ReadOnlyRoots(isolate).null_value());
return;
}
// TODO(titzer): Change this to MaybeHandle<WasmExportedFunction>
DCHECK(WasmExportedFunction::IsWasmExportedFunction(*function));
auto exported_function = Handle<WasmExportedFunction>::cast(function);
Handle<WasmInstanceObject> other_instance(exported_function->instance(),
isolate);
int func_index = exported_function->function_index();
auto* wasm_function = &other_instance->module()->functions[func_index];
DCHECK_NOT_NULL(wasm_function);
DCHECK_NOT_NULL(wasm_function->sig);
Address call_target = exported_function->GetWasmCallTarget();
UpdateDispatchTables(isolate, table, table_index, wasm_function->sig,
handle(exported_function->instance(), isolate),
call_target);
array->set(table_index, *function);
}
void WasmTableObject::UpdateDispatchTables(
Isolate* isolate, Handle<WasmTableObject> table, int table_index,
wasm::FunctionSig* sig, Handle<WasmInstanceObject> from_instance,
Address call_target) {
// We simply need to update the IFTs for each instance that imports
// this table.
Handle<FixedArray> dispatch_tables(table->dispatch_tables(), isolate);
DCHECK_EQ(0, dispatch_tables->length() % kDispatchTableNumElements);
for (int i = 0; i < dispatch_tables->length();
i += kDispatchTableNumElements) {
Handle<WasmInstanceObject> to_instance(
WasmInstanceObject::cast(
dispatch_tables->get(i + kDispatchTableInstanceOffset)),
isolate);
// Note that {SignatureMap::Find} may return {-1} if the signature is
// not found; it will simply never match any check.
auto sig_id = to_instance->module()->signature_map.Find(*sig);
IndirectFunctionTableEntry(to_instance, table_index)
.set(sig_id, *from_instance, call_target);
}
}
void WasmTableObject::ClearDispatchTables(Isolate* isolate,
Handle<WasmTableObject> table,
int index) {
Handle<FixedArray> dispatch_tables(table->dispatch_tables(), isolate);
DCHECK_EQ(0, dispatch_tables->length() % kDispatchTableNumElements);
for (int i = 0; i < dispatch_tables->length();
i += kDispatchTableNumElements) {
Handle<WasmInstanceObject> target_instance(
WasmInstanceObject::cast(
dispatch_tables->get(i + kDispatchTableInstanceOffset)),
isolate);
DCHECK_LT(index, target_instance->indirect_function_table_size());
IndirectFunctionTableEntry(target_instance, index).clear();
}
}
namespace {
MaybeHandle<JSArrayBuffer> GrowMemoryBuffer(Isolate* isolate,
Handle<JSArrayBuffer> old_buffer,
uint32_t pages,
uint32_t maximum_pages) {
if (!old_buffer->is_growable()) return {};
void* old_mem_start = old_buffer->backing_store();
size_t old_size = old_buffer->byte_length();
CHECK_GE(wasm::kV8MaxWasmMemoryBytes, old_size);
CHECK_EQ(0, old_size % wasm::kWasmPageSize);
size_t old_pages = old_size / wasm::kWasmPageSize;
if (old_pages > maximum_pages || // already reached maximum
(pages > maximum_pages - old_pages) || // exceeds remaining
(pages > FLAG_wasm_max_mem_pages - old_pages)) { // exceeds limit
return {};
}
size_t new_size =
static_cast<size_t>(old_pages + pages) * wasm::kWasmPageSize;
CHECK_GE(wasm::kV8MaxWasmMemoryBytes, new_size);
// Reusing the backing store from externalized buffers causes problems with
// Blink's array buffers. The connection between the two is lost, which can
// lead to Blink not knowing about the other reference to the buffer and
// freeing it too early.
if (!old_buffer->is_external() &&
((new_size < old_buffer->allocation_length()) || old_size == new_size)) {
if (old_size != new_size) {
DCHECK_NOT_NULL(old_buffer->backing_store());
// If adjusting permissions fails, propagate error back to return
// failure to grow.
if (!i::SetPermissions(GetPlatformPageAllocator(), old_mem_start,
new_size, PageAllocator::kReadWrite)) {
return {};
}
reinterpret_cast<v8::Isolate*>(isolate)
->AdjustAmountOfExternalAllocatedMemory(pages * wasm::kWasmPageSize);
}
// NOTE: We must allocate a new array buffer here because the spec
// assumes that ArrayBuffers do not change size.
void* backing_store = old_buffer->backing_store();
bool is_external = old_buffer->is_external();
// Disconnect buffer early so GC won't free it.
i::wasm::DetachMemoryBuffer(isolate, old_buffer, false);
Handle<JSArrayBuffer> new_buffer =
wasm::SetupArrayBuffer(isolate, backing_store, new_size, is_external);
return new_buffer;
} else {
// We couldn't reuse the old backing store, so create a new one and copy the
// old contents in.
Handle<JSArrayBuffer> new_buffer;
if (!wasm::NewArrayBuffer(isolate, new_size).ToHandle(&new_buffer)) {
return {};
}
wasm::WasmMemoryTracker* const memory_tracker =
isolate->wasm_engine()->memory_tracker();
// If the old buffer had full guard regions, we can only safely use the new
// buffer if it also has full guard regions. Otherwise, we'd have to
// recompile all the instances using this memory to insert bounds checks.
if (memory_tracker->HasFullGuardRegions(old_mem_start) &&
!memory_tracker->HasFullGuardRegions(new_buffer->backing_store())) {
return {};
}
if (old_size == 0) return new_buffer;
memcpy(new_buffer->backing_store(), old_mem_start, old_size);
DCHECK(old_buffer.is_null() || !old_buffer->is_shared());
constexpr bool free_memory = true;
i::wasm::DetachMemoryBuffer(isolate, old_buffer, free_memory);
return new_buffer;
}
}
// May GC, because SetSpecializationMemInfoFrom may GC
void SetInstanceMemory(Handle<WasmInstanceObject> instance,
Handle<JSArrayBuffer> buffer) {
instance->SetRawMemory(reinterpret_cast<byte*>(buffer->backing_store()),
buffer->byte_length());
#if DEBUG
if (!FLAG_mock_arraybuffer_allocator) {
// To flush out bugs earlier, in DEBUG mode, check that all pages of the
// memory are accessible by reading and writing one byte on each page.
// Don't do this if the mock ArrayBuffer allocator is enabled.
byte* mem_start = instance->memory_start();
size_t mem_size = instance->memory_size();
for (size_t offset = 0; offset < mem_size; offset += wasm::kWasmPageSize) {
byte val = mem_start[offset];
USE(val);
mem_start[offset] = val;
}
}
#endif
}
} // namespace
Handle<WasmMemoryObject> WasmMemoryObject::New(
Isolate* isolate, MaybeHandle<JSArrayBuffer> maybe_buffer,
int32_t maximum) {
// TODO(kschimpf): Do we need to add an argument that defines the
// style of memory the user prefers (with/without trap handling), so
// that the memory will match the style of the compiled wasm module.
// See issue v8:7143
Handle<JSFunction> memory_ctor(
isolate->native_context()->wasm_memory_constructor(), isolate);
auto memory_obj = Handle<WasmMemoryObject>::cast(
isolate->factory()->NewJSObject(memory_ctor, TENURED));
Handle<JSArrayBuffer> buffer;
if (!maybe_buffer.ToHandle(&buffer)) {
// If no buffer was provided, create a 0-length one.
buffer = wasm::SetupArrayBuffer(isolate, nullptr, 0, false);
}
memory_obj->set_array_buffer(*buffer);
memory_obj->set_maximum_pages(maximum);
return memory_obj;
}
uint32_t WasmMemoryObject::current_pages() {
return static_cast<uint32_t>(array_buffer()->byte_length() /
wasm::kWasmPageSize);
}
bool WasmMemoryObject::has_full_guard_region(Isolate* isolate) {
const wasm::WasmMemoryTracker::AllocationData* allocation =
isolate->wasm_engine()->memory_tracker()->FindAllocationData(
array_buffer()->backing_store());
CHECK_NOT_NULL(allocation);
Address allocation_base =
reinterpret_cast<Address>(allocation->allocation_base);
Address buffer_start = reinterpret_cast<Address>(allocation->buffer_start);
// Return whether the allocation covers every possible Wasm heap index.
//
// We always have the following relationship:
// allocation_base <= buffer_start <= buffer_start + memory_size <=
// allocation_base + allocation_length
// (in other words, the buffer fits within the allocation)
//
// The space between buffer_start + memory_size and allocation_base +
// allocation_length is the guard region. Here we make sure the guard region
// is large enough for any Wasm heap offset.
return buffer_start + wasm::kWasmMaxHeapOffset <=
allocation_base + allocation->allocation_length;
}
void WasmMemoryObject::AddInstance(Isolate* isolate,
Handle<WasmMemoryObject> memory,
Handle<WasmInstanceObject> instance) {
Handle<WeakArrayList> old_instances =
memory->has_instances()
? Handle<WeakArrayList>(memory->instances(), isolate)
: handle(ReadOnlyRoots(isolate->heap()).empty_weak_array_list(),
isolate);
Handle<WeakArrayList> new_instances = WeakArrayList::AddToEnd(
isolate, old_instances, MaybeObjectHandle::Weak(instance));
memory->set_instances(*new_instances);
Handle<JSArrayBuffer> buffer(memory->array_buffer(), isolate);
SetInstanceMemory(instance, buffer);
}
void WasmMemoryObject::RemoveInstance(Handle<WasmMemoryObject> memory,
Handle<WasmInstanceObject> instance) {
if (memory->has_instances()) {
memory->instances()->RemoveOne(MaybeObjectHandle::Weak(instance));
}
}
// static
int32_t WasmMemoryObject::Grow(Isolate* isolate,
Handle<WasmMemoryObject> memory_object,
uint32_t pages) {
Handle<JSArrayBuffer> old_buffer(memory_object->array_buffer(), isolate);
if (!old_buffer->is_growable()) return -1;
size_t old_size = old_buffer->byte_length();
DCHECK_EQ(0, old_size % wasm::kWasmPageSize);
Handle<JSArrayBuffer> new_buffer;
uint32_t maximum_pages = FLAG_wasm_max_mem_pages;
if (memory_object->has_maximum_pages()) {
maximum_pages = Min(FLAG_wasm_max_mem_pages,
static_cast<uint32_t>(memory_object->maximum_pages()));
}
if (!GrowMemoryBuffer(isolate, old_buffer, pages, maximum_pages)
.ToHandle(&new_buffer)) {
return -1;
}
if (memory_object->has_instances()) {
Handle<WeakArrayList> instances(memory_object->instances(), isolate);
for (int i = 0; i < instances->length(); i++) {
MaybeObject* elem = instances->Get(i);
HeapObject* heap_object;
if (elem->GetHeapObjectIfWeak(&heap_object)) {
Handle<WasmInstanceObject> instance(
WasmInstanceObject::cast(heap_object), isolate);
SetInstanceMemory(instance, new_buffer);
} else {
DCHECK(elem->IsCleared());
}
}
}
memory_object->set_array_buffer(*new_buffer);
return static_cast<uint32_t>(old_size / wasm::kWasmPageSize);
}
// static
MaybeHandle<WasmGlobalObject> WasmGlobalObject::New(
Isolate* isolate, MaybeHandle<JSArrayBuffer> maybe_buffer,
wasm::ValueType type, int32_t offset, bool is_mutable) {
Handle<JSFunction> global_ctor(
isolate->native_context()->wasm_global_constructor(), isolate);
auto global_obj = Handle<WasmGlobalObject>::cast(
isolate->factory()->NewJSObject(global_ctor));
uint32_t type_size = wasm::ValueTypes::ElementSizeInBytes(type);
Handle<JSArrayBuffer> buffer;
if (!maybe_buffer.ToHandle(&buffer)) {
// If no buffer was provided, create one long enough for the given type.
buffer =
isolate->factory()->NewJSArrayBuffer(SharedFlag::kNotShared, TENURED);
const bool initialize = true;
if (!JSArrayBuffer::SetupAllocatingData(buffer, isolate, type_size,
initialize)) {
return {};
}
}
// Check that the offset is in bounds.
CHECK_LE(offset + type_size, buffer->byte_length());
global_obj->set_array_buffer(*buffer);
global_obj->set_flags(0);
global_obj->set_type(type);
global_obj->set_offset(offset);
global_obj->set_is_mutable(is_mutable);
return global_obj;
}
void IndirectFunctionTableEntry::clear() {
instance_->indirect_function_table_sig_ids()[index_] = -1;
instance_->indirect_function_table_targets()[index_] = 0;
instance_->indirect_function_table_instances()->set(
index_, ReadOnlyRoots(instance_->GetIsolate()).undefined_value());
}
void IndirectFunctionTableEntry::set(int sig_id, WasmInstanceObject* instance,
Address call_target) {
TRACE_IFT("IFT entry %p[%d] = {sig_id=%d, instance=%p, target=%" PRIuPTR
"}\n",
*instance_, index_, sig_id, instance, call_target);
instance_->indirect_function_table_sig_ids()[index_] = sig_id;
instance_->indirect_function_table_targets()[index_] = call_target;
instance_->indirect_function_table_instances()->set(index_, instance);
}
WasmInstanceObject* IndirectFunctionTableEntry::instance() {
return WasmInstanceObject::cast(
instance_->indirect_function_table_instances()->get(index_));
}
int IndirectFunctionTableEntry::sig_id() {
return instance_->indirect_function_table_sig_ids()[index_];
}
Address IndirectFunctionTableEntry::target() {
return instance_->indirect_function_table_targets()[index_];
}
void ImportedFunctionEntry::set_wasm_to_js(
JSReceiver* callable, const wasm::WasmCode* wasm_to_js_wrapper) {
TRACE_IFT("Import callable %p[%d] = {callable=%p, target=%p}\n", *instance_,
index_, callable, wasm_to_js_wrapper->instructions().start());
DCHECK_EQ(wasm::WasmCode::kWasmToJsWrapper, wasm_to_js_wrapper->kind());
instance_->imported_function_instances()->set(index_, *instance_);
instance_->imported_function_callables()->set(index_, callable);
instance_->imported_function_targets()[index_] =
wasm_to_js_wrapper->instruction_start();
}
void ImportedFunctionEntry::set_wasm_to_wasm(WasmInstanceObject* instance,
Address call_target) {
TRACE_IFT("Import WASM %p[%d] = {instance=%p, target=%" PRIuPTR "}\n",
*instance_, index_, instance, call_target);
instance_->imported_function_instances()->set(index_, instance);
instance_->imported_function_callables()->set(
index_, instance_->GetReadOnlyRoots().undefined_value());
instance_->imported_function_targets()[index_] = call_target;
}
WasmInstanceObject* ImportedFunctionEntry::instance() {
return WasmInstanceObject::cast(
instance_->imported_function_instances()->get(index_));
}
JSReceiver* ImportedFunctionEntry::callable() {
return JSReceiver::cast(
instance_->imported_function_callables()->get(index_));
}
Address ImportedFunctionEntry::target() {
return instance_->imported_function_targets()[index_];
}
bool ImportedFunctionEntry::is_js_receiver_entry() {
return instance_->imported_function_callables()->get(index_)->IsJSReceiver();
}
bool WasmInstanceObject::EnsureIndirectFunctionTableWithMinimumSize(
Handle<WasmInstanceObject> instance, uint32_t minimum_size) {
uint32_t old_size = instance->indirect_function_table_size();
if (old_size >= minimum_size) return false; // Nothing to do.
Isolate* isolate = instance->GetIsolate();
HandleScope scope(isolate);
auto native_allocations = GetNativeAllocations(*instance);
native_allocations->resize_indirect_function_table(isolate, instance,
minimum_size);
return true;
}
void WasmInstanceObject::SetRawMemory(byte* mem_start, size_t mem_size) {
CHECK_LE(mem_size, wasm::kV8MaxWasmMemoryBytes);
#if V8_HOST_ARCH_64_BIT
uint64_t mem_mask64 = base::bits::RoundUpToPowerOfTwo64(mem_size) - 1;
set_memory_start(mem_start);
set_memory_size(mem_size);
set_memory_mask(mem_mask64);
#else
// Must handle memory > 2GiB specially.
CHECK_LE(mem_size, size_t{kMaxUInt32});
uint32_t mem_mask32 =
(mem_size > 2 * size_t{GB})
? 0xFFFFFFFFu
: base::bits::RoundUpToPowerOfTwo32(static_cast<uint32_t>(mem_size)) -
1;
set_memory_start(mem_start);
set_memory_size(mem_size);
set_memory_mask(mem_mask32);
#endif
}
const WasmModule* WasmInstanceObject::module() {
return module_object()->module();
}
Handle<WasmDebugInfo> WasmInstanceObject::GetOrCreateDebugInfo(
Handle<WasmInstanceObject> instance) {
if (instance->has_debug_info()) {
return handle(instance->debug_info(), instance->GetIsolate());
}
Handle<WasmDebugInfo> new_info = WasmDebugInfo::New(instance);
DCHECK(instance->has_debug_info());
return new_info;
}
Handle<WasmInstanceObject> WasmInstanceObject::New(
Isolate* isolate, Handle<WasmModuleObject> module_object) {
Handle<JSFunction> instance_cons(
isolate->native_context()->wasm_instance_constructor(), isolate);
Handle<JSObject> instance_object =
isolate->factory()->NewJSObject(instance_cons, TENURED);
Handle<WasmInstanceObject> instance(
reinterpret_cast<WasmInstanceObject*>(*instance_object), isolate);
// Initialize the imported function arrays.
auto module = module_object->module();
auto num_imported_functions = module->num_imported_functions;
auto num_imported_mutable_globals = module->num_imported_mutable_globals;
size_t native_allocations_size = EstimateNativeAllocationsSize(module);
auto native_allocations = Managed<WasmInstanceNativeAllocations>::Allocate(
isolate, native_allocations_size, instance, num_imported_functions,
num_imported_mutable_globals);
instance->set_managed_native_allocations(*native_allocations);
Handle<FixedArray> imported_function_instances =
isolate->factory()->NewFixedArray(num_imported_functions);
instance->set_imported_function_instances(*imported_function_instances);
Handle<FixedArray> imported_function_callables =
isolate->factory()->NewFixedArray(num_imported_functions);
instance->set_imported_function_callables(*imported_function_callables);
Handle<Code> centry_stub = CodeFactory::CEntry(isolate);
instance->set_centry_stub(*centry_stub);
instance->SetRawMemory(nullptr, 0);
instance->set_roots_array_address(
reinterpret_cast<Address>(isolate->heap()->roots_array_start()));
instance->set_stack_limit_address(
isolate->stack_guard()->address_of_jslimit());
instance->set_real_stack_limit_address(
isolate->stack_guard()->address_of_real_jslimit());
instance->set_globals_start(nullptr);
instance->set_indirect_function_table_size(0);
instance->set_indirect_function_table_sig_ids(nullptr);
instance->set_indirect_function_table_targets(nullptr);
instance->set_native_context(*isolate->native_context());
instance->set_module_object(*module_object);
instance->set_undefined_value(ReadOnlyRoots(isolate).undefined_value());
instance->set_null_value(ReadOnlyRoots(isolate).null_value());
instance->set_jump_table_start(
module_object->native_module()->jump_table_start());
// Insert the new instance into the modules weak list of instances.
// TODO(mstarzinger): Allow to reuse holes in the {WeakArrayList} below.
Handle<WeakArrayList> weak_instance_list(module_object->weak_instance_list(),
isolate);
weak_instance_list = WeakArrayList::AddToEnd(
isolate, weak_instance_list, MaybeObjectHandle::Weak(instance));
module_object->set_weak_instance_list(*weak_instance_list);
return instance;
}
Address WasmInstanceObject::GetCallTarget(uint32_t func_index) {
wasm::NativeModule* native_module = module_object()->native_module();
if (func_index < native_module->num_imported_functions()) {
return imported_function_targets()[func_index];
}
return native_module->GetCallTargetForFunction(func_index);
}
// static
Handle<WasmExceptionObject> WasmExceptionObject::New(
Isolate* isolate, const wasm::FunctionSig* sig,
Handle<HeapObject> exception_tag) {
Handle<JSFunction> exception_cons(
isolate->native_context()->wasm_exception_constructor(), isolate);
Handle<JSObject> exception_object =
isolate->factory()->NewJSObject(exception_cons, TENURED);
Handle<WasmExceptionObject> exception =
Handle<WasmExceptionObject>::cast(exception_object);
// Serialize the signature.
DCHECK_EQ(0, sig->return_count());
DCHECK_LE(sig->parameter_count(), std::numeric_limits<int>::max());
int sig_size = static_cast<int>(sig->parameter_count());
Handle<PodArray<wasm::ValueType>> serialized_sig =
PodArray<wasm::ValueType>::New(isolate, sig_size, TENURED);
int index = 0; // Index into the {PodArray} above.
for (wasm::ValueType param : sig->parameters()) {
serialized_sig->set(index++, param);
}
exception->set_serialized_signature(*serialized_sig);
exception->set_exception_tag(*exception_tag);
return exception;
}
bool WasmExceptionObject::IsSignatureEqual(const wasm::FunctionSig* sig) {
DCHECK_EQ(0, sig->return_count());
DCHECK_LE(sig->parameter_count(), std::numeric_limits<int>::max());
int sig_size = static_cast<int>(sig->parameter_count());
if (sig_size != serialized_signature()->length()) return false;
for (int index = 0; index < sig_size; ++index) {
if (sig->GetParam(index) != serialized_signature()->get(index)) {
return false;
}
}
return true;
}
bool WasmExportedFunction::IsWasmExportedFunction(Object* object) {
if (!object->IsJSFunction()) return false;
JSFunction* js_function = JSFunction::cast(object);
if (Code::JS_TO_WASM_FUNCTION != js_function->code()->kind()) return false;
DCHECK(js_function->shared()->HasWasmExportedFunctionData());
return true;
}
WasmExportedFunction* WasmExportedFunction::cast(Object* object) {
DCHECK(IsWasmExportedFunction(object));
return reinterpret_cast<WasmExportedFunction*>(object);
}
WasmInstanceObject* WasmExportedFunction::instance() {
return shared()->wasm_exported_function_data()->instance();
}
int WasmExportedFunction::function_index() {
return shared()->wasm_exported_function_data()->function_index();
}
Handle<WasmExportedFunction> WasmExportedFunction::New(
Isolate* isolate, Handle<WasmInstanceObject> instance,
MaybeHandle<String> maybe_name, int func_index, int arity,
Handle<Code> export_wrapper) {
DCHECK_EQ(Code::JS_TO_WASM_FUNCTION, export_wrapper->kind());
int num_imported_functions = instance->module()->num_imported_functions;
int jump_table_offset = -1;
if (func_index >= num_imported_functions) {
ptrdiff_t jump_table_diff =
instance->module_object()->native_module()->jump_table_offset(
func_index);
DCHECK(jump_table_diff >= 0 && jump_table_diff <= INT_MAX);
jump_table_offset = static_cast<int>(jump_table_diff);
}
Handle<WasmExportedFunctionData> function_data =
Handle<WasmExportedFunctionData>::cast(isolate->factory()->NewStruct(
WASM_EXPORTED_FUNCTION_DATA_TYPE, TENURED));
function_data->set_wrapper_code(*export_wrapper);
function_data->set_instance(*instance);
function_data->set_jump_table_offset(jump_table_offset);
function_data->set_function_index(func_index);
Handle<String> name;
if (!maybe_name.ToHandle(&name)) {
EmbeddedVector<char, 16> buffer;
int length = SNPrintF(buffer, "%d", func_index);
name = isolate->factory()
->NewStringFromOneByte(
Vector<uint8_t>::cast(buffer.SubVector(0, length)))
.ToHandleChecked();
}
NewFunctionArgs args = NewFunctionArgs::ForWasm(
name, function_data, isolate->sloppy_function_without_prototype_map());
Handle<JSFunction> js_function = isolate->factory()->NewFunction(args);
// According to the spec, exported functions should not have a [[Construct]]
// method.
DCHECK(!js_function->IsConstructor());
js_function->shared()->set_length(arity);
js_function->shared()->set_internal_formal_parameter_count(arity);
return Handle<WasmExportedFunction>::cast(js_function);
}
Address WasmExportedFunction::GetWasmCallTarget() {
return instance()->GetCallTarget(function_index());
}
#undef TRACE
#undef TRACE_IFT
} // namespace internal
} // namespace v8